The prior art is replete with devices designed to assist individuals in carrying various objects. As the size and weight of a particular object increases, difficulties increase as well. By way of example only, and not by limitation, a difficulty exists in the prior art with attempting to maneuver foundations and, even more particularly, house slabs. The state of art for moving house slabs is represented by U.S. Pat. No. 4,320,607 to Eubank. The Eubank device utilizes a trailer unit with axles located beneath the foundation/slab on each end. This requires the slab to be lifted up and over the axles and then down onto the trailer. This results in the slab being carried high off the ground. The top of the slab for example may be as much as fifty to sixty inches off the ground in the loaded position. This causes instability of an already heavy load and limits the height of any structure that might be carried on the slab, such as a mobile home.
Once the slab has been moved to the proper location, the slab must again be raised up and over the axles so that the trailer may be removed and the slab placed on the ground. Eubank's device utilizes jacks on each corner of the slab to raise the slab off the trailer. This is a dangerous proposition since the slab must be raised above the height of the axles and tires in order for the trailer to be removed. Also, four jacks are required to be used in whatever location the slab is to be placed. This may be uneven ground which again adds to the instability, as the entire slab is lifted on only four independent points. That is, a separate jack is mounted to opposite ends of two steel support spreaders and then separately handled by lifting and attaching them by hard attachment, such as bolts, to the ends of the slab. Further, with equipment located underneath the slab, it is inevitable that someone will be required to get underneath the slab in order to position a piece of equipment while it is in the high and dangerously unstable position.
A further difficulty arises when handling pre-stressed and post tensioned concrete slab products. Pre-stressed and post tensioned concrete products are engineered to be lifted, carried, and supported near their ends. The Eubank device positioned the trailer units at the ends of the slab being transported for just this purpose. The support points in Eubank's device had to be within approximately four feet of the ends or the slab would have broken.
Other carriers have been designed to lift and transport essentially rigid, inflexible containers, such as shipping containers. Concha et al., U.S. Pat. No. 4,297,068, discloses such a shipping container transporter designed to connect to a hard attachment on the rigid container. As the term is used herein, a hard attachment is an attachment such as a bolt, screw, weld or the like that serves to prevent any movement of the attachment once made. Such hard attachments have proven to be the source of failure in prior art devices for transporting semi-rigid, flexible objects such as foundations and slabs, for example only and not by limitation. On the other hand, as used herein “compressive engagement” is a connection to the object to be carried that allows some movement while connected. For example only and not by way of limitation, compressive engagement includes attachments to objects by means of compression.
Thus, there is a need in the art for providing a carrier apparatus and method which enables a user to transport a slab at a minimum distance above the ground and in such a manner that the integrity of the slab is not threatened.